I have done some work to upgrade my YPPH feed. Previously it was a feed that scanned between APP,TWR and DEP on the one stream.
It now has 3 separate streams and a 4th stream will be added in the coming weeks.
Antenna is on the 4th floor of my apartment building (I'm on the 1st floor), with a LMR400 cable running down. Antenna is a MobileOne SW2-124 slimjim.
LMR400 is a very low loss coaxial cable, same thickness as RG213. The signal is split 4 ways and feeds to the 3 scanners:
Scanners from left to right are:
Uniden UBCT8 YPPH DEP 118.7Mhz
Uniden UBCD396XT YPPH TWR 120.5Mhz
Uniden 3000XLT YPPH APP 123.6Mhz
Then the audio goes from the scanners to 3 x Creative Labs Sound Blaster Play USB dongles, with audio in jacks, which are connected to a 10 port powered USB hub which is connected to the Raspberry Pi and networked to my ADSL router.